The ground state of metamagnetic materials can be precisely controlled by application of magnetic field, making them exciting candidates for spintronic applications. In itinerant metamagnets, such as Sr₄Ru₃O₁₀, understanding their electronic structure is crucial for successfull manipulation and tuning of their magnetic properties.

I will show measurements using quasiparticle interference imaging in a low-temperature scanning tunnelling microscope to study the electronic structure of Sr₄Ru₃O₁₀ in magnetic field. We find a strongly anisotropic response to the in-plane magnetic field, suggesting an unusually strong effect of the orthorhombic distortion on the electronic structure. Using DFT calculations, we can model the QPI signal and find the Fermi surface dominated by bands of spin-minority character, putting constraints on theories for the origin of the metamagnetic transition. Additionally, by including strong spin-orbit coupling in the tight-binding framework, we are able to qualitatively reproduce the observed tunnnelling spectra.